SSRF (Server-Side Request Forgery) in @zereight/mcp-gitlab (CVE-2026-61559)
Summary
SSRF in @zereight/mcp-gitlab (CVE-2026-61559). Confidential information can be exposed externally. Exploitable via GET /api/v4/projects/1/issues. Mitigation: upgrade to 2.1.27 or later.
Original description
The description as published by the source.
Server-Side Request Forgery via X-GitLab-API-URL Header Allows Credential Theft
Affected
- Repository:
zereight/gitlab-mcp - Affected versions: All versions through commit
74a8c83 - Patched versions: None at time of report
Severity
High. CVSS v3.1 8.5 (AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:N)
Description
When the environment variable ENABLE_DYNAMIC_API_URL=true is set, the server
reads the X-GitLab-API-URL HTTP request header and uses it as the base URL for
all outbound GitLab API calls made within that request. The server validates that
the value is a well-formed URL (new URL(dynamicApiUrl)) but applies no
allowlist or hostname restriction. The server then attaches the victim's
Private-Token to every outbound fetch that uses the redirected URL.
Any caller who can reach the HTTP transport can set X-GitLab-API-URL to an
attacker-controlled host. The next GitLab API call the server makes delivers the
victim's token to that host.
The vulnerable code appears at two locations.
SSE handler (index.ts:11541):
const dynamicApiUrl = req.headers["x-gitlab-api-url"]?.trim();
if (ENABLE_DYNAMIC_API_URL && dynamicApiUrl) {
apiUrl = normalizeGitLabApiUrl(dynamicApiUrl); // no allowlist check
}
Streamable HTTP handler (index.ts:11787), inside parseAuthHeaders:
const dynamicApiUrl = req.headers["x-gitlab-api-url"]?.trim();
if (ENABLE_DYNAMIC_API_URL && dynamicApiUrl) {
new URL(dynamicApiUrl);…
Source: NIST National Vulnerability Database NVD GitHub Advisory
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2026-61559 has been found in @zereight/mcp-gitlab.
Attackers can target a specific entry point like GET /api/v4/projects/1/issues over the network to misuse the product.
Confidential information can be exposed externally. CVSS score: 9.6/10.
What to do: upgrade @zereight/mcp-gitlab to 2.1.27 or later.
If unsure, ask your IT team or search "@zereight/mcp-gitlab CVE-2026-61559" on the vendor's site.
CVE-2026-61559 (@zereight/mcp-gitlab) — CWE-918 / CVSS v3 9.6
Attack vector: remote (network-reachable) / no user interaction
Attack surface: GET /api/v4/projects/1/issues / parseAuthHeaders / apiUrl / ENABLE_DYNAMIC_API_URL
Patched: 2.1.27 — apply immediately
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
SSRF (CWE-918) exists in @zereight/mcp-gitlab. Attackers reach the vulnerable code path via GET /api/v4/projects/1/issues.
Check the vendor advisory for the affected versions of @zereight/mcp-gitlab. Attack surface: GET /api/v4/projects/1/issues / parseAuthHeaders / apiUrl / ENABLE_DYNAMIC_API_URL.
Severity: Critical (CVSS 9.6/10). Confidential information can be exposed externally.
Update to 2.1.27.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual GET /api/v4/projects/1/issues requests with malformed payloads or SQL meta-characters. Run grep -r '@zereight/mcp-gitlab' . against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
-
1Identify exposure identify
grep -r '@zereight/mcp-gitlab' . | grep -v node_modulesリポジトリと本番環境の依存ファイル (package-lock.json / requirements.txt / go.sum / Gemfile.lock 等) で
@zereight/mcp-gitlabを grep し、稼働しているサービス・バージョンを把握する。 -
2Hunt for indicators of compromise detect
grep 'GET /api/v4/projects/1/issues' /var/log/nginx/access.log | grep -E '(unusual_payload|sqli_pattern)'アクセスログで
GET /api/v4/projects/1/issuesへの異常なリクエスト (不正な認証ヘッダ・SQLメタ文字)を過去 30〜90日分捜索。WAF/SIEM があれば該当パスのアラート発火履歴を確認。 -
3Apply patch patch
Upgrade @zereight/mcp-gitlab to 2.1.27ステージング環境で 2.1.27 に上げて回帰テスト → 本番反映。回帰テストはアプリの主要ハッピーパスと、Step 2 で見つけた異常検知の続報チェックを含めること。
-
4Post-deployment verification verify
Replay attack against GET /api/v4/projects/1/issues on staging to confirm patch closes the vectorパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番では Step 2 と同じログクエリでアラート再発が無いか継続監視。
Affected packages
References
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